import java.util.concurrent.CancellationException;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.Executor;
import java.util.concurrent.Future;
import java.util.concurrent.RejectedExecutionException;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;
import java.util.concurrent.atomic.AtomicInteger;

import java.util.concurrent.CountDownLatch;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.Executor;
import java.util.concurrent.Future;
import java.util.concurrent.RejectedExecutionException;
import java.util.concurrent.atomic.AtomicReference;
import org.jspecify.annotations.Nullable;

/**
 * A step in a pipeline of an asynchronous computation. When the last step in the computation is

    implementation("com.squareup.okio:okio:1.15.0")
    ```

 *  Fix: Handle dispatcher executor shutdowns gracefully. When there aren't any threads to carry a
    call its callback now gets a `RejectedExecutionException`.
 *  Fix: Don't permanently cache responses with `Cache-Control: immutable`. We misunderstood the
    original `immutable` proposal!